Burner for liquid fuel



Oct. 4,1927.

J. H. GRAY- BURNER FOR LIQUID FUEL Filed April 21, 1922 2 Sheets-Sheet l @J 50 24 f 70 5o 5 (I 5 6'0 60 $22 713. 20" Q 5 7 I 54 .1 I I v MENTOR. c/AMES [YGRA Y.

ATTORNEY.

Oct. 4, 1927.

J. H. GRAY BURNER FOR LIQUID FUEL & W M m N% M w 3 m H m w i J 5 my M 2 g q .Q N M lm W M w a row M E. Q N\\ Q 5 a x W Z4 ,Y QA M [lIlIII l |i m J A IE ww H E 1 k mwwx Ly MWV bhx wb v .Q .kL Qm n g g Q @w N9 w & Q NQ g R a g W QM Q m Q 1 Patented Get, 4, 1927.

JAMES H. GRAY, OF NEW YOBK, N. Y.

BURNER FOR LIQUID FUEL.

A lication filed April 21, 1922. semi no. 555,803.

products of combustion or waste gases on the outgoing end of the furnace are used to heat regenerative chambers which are subsequently used to pre-heat the air on the incoming end of the furnace.

Oil and tar are both desirable fuels and they can be introduced singly or may be mixed with gas such as by-product. coke oven gas. Tar and fuel oils such as are usually .used in metallurgical practice are so viscous at ordinary temperatures that it is necessary to preheat them in order to circulate these fuels through pipes and inject them into the furnace through burners. For this reason it has been necessary heretofore to store the tar or oil in tanks heated by means of steam coils or the like. In order to properly atomize the fuel it has been necessary, heretofore,

' to resort to the use of a blast of steam or compressed air.

In reversing furnaces-at onetime it was the practice to withdraw the burner from the outgoing end of the furnace to prevent its destruction by the excessive heat and to mount it at the incoming end of the furnace at each reversing period. This proved to be a laborious and costly operation. Later the burners were left in place at both ends of the furnace and to prevent their destruction by the excessive heat water cooling devices were used.

The use of steam or air for atomizing the fuel and the use of water for cooling the burner added greatly to the cost of operation of burners heretofore proposed. In fact in some installations this cost is as high as onequarter of the value of the fuel used.

My improved burner eliminates the neces- 4 sity of providing steam or air pressure to atomize the fuel and also eliminates the use of water for cooling the burner, as well as the necessary apparatus to control the steam or air each time the furnace is reversed and also relieves the operator of the work of going in between the hot furnaces to adjust the flow of the air or steam. heretofore used for atomizing the fuel.

In my mproved burner the fuel is atomized mechanically without the use of steam or air and the burner itself is cooled by circulating the fuel continuously through the burners at both ends of the furnace.

The invention is illustrated in the accompanying drawings in which I Fig. 1 shows diagrammaticall a plurality of metallurgical furnaces embo ying my in- JBIllZlOIl;

F. 1g. 2 is a longitudinal section through one end of a furnace equipped with the improved type of burner;

Fig. 3 is a detail Fig. 1;

Fig. 4 is an enlarged longitudinal sect-ion showing a burner embodyin my invention;

Fig. 5 is a section throug the spray nozzle of the burner on line 5-5 of Fig. 4; Fig. 6 is an end view of a member shown in Fig. 4; i

Fig. 7 is a detail of a portion of the spray nozzle as viewed from line 5--5 of Fig. 4.

In modern steel plants the open hearth of a valve shown in furnaces are usually arranged in batteries of. from ten to twenty furnaces each, all drawing fuel from a common supply tank. Fig. 1 illustrates diagrammatically one complete furnace 10 of such a battery and portions of two other furnaces 12 and 14 adaoent thereto. Fuel is supplied to all of the furnaces from a tank 16 through a supply main 18 which has a branch 20 leading to each furnace. A pump 15 is connected by a branch 17 with the tank Y16 and the supply main 18 is adapted to maintain a pressure of approximately 80 pounds in said main and to circulate the fuelin thedirection of the arrows. A check valve 19 is located in the branch 17 between thepump and the tank,. and a gauge 21 is provided in the main 18 to indicate the pressure. The pipe 20 connects with a pipe 22 leadin to a threeway control valve 241 from whic extends branches 26 and 28. The three-way valve is provided with a plug 30 having a port 32 therein adapted to establish communication from :the pipe 22 to either of the pipes '26 01-28 as desired. Pipes 26.

and 28 connect theburners 34 and 36 respectively at opposite ends of the furnace with an inlet port 38-.(Fig. 4) formed in each burner. Pipes wand 42connect an outlet port 44 of each burner with a return fuel main 46. By-pass branches 48 and'50 are connected around the three-way valveso that fuel may be supplied to the pipes 26 and 28 regardless of the position of the threeway valve. These by-pass pipes are, provided with pressure auges 52 and 54 and throttle valves 56 an 58.

The burners are so constructed that the fuel is continuously circulated through the burners 34 and 36 at the opposite ends of the furnace regardless of the position of the three-way valve so that the fuel is utilized to cool the burners and prevent their destruction. This also keeps the fuel in such liquid condition that it can readily be circulated through the piping system and atomized without the utilization of steam or compressed air. k

The arrangement is such that when the plug 30 of the three-way valve 24 is in one position, the fuel will be injected into one end of the furnace from burner 34 and a cert-ain amount of fuel will circulate through the other burner 36 without being injected into the furnace. When the three-way valve is shifted to its other position, the fuel will be injected from the burner 36 at the opposite end of the furnace and at such time there will be a circulation of fuel through the opposite burner 34. This operation is made possible by use of the improved burner I am now about to describe.

The burners 34 and 36 are duplicates, and therefore, a description of one will sufiice for both. Each burner comprises a body portion 60 having a head 62lsecured thereto which is formed with an inlet port 38. The body portion 60 is formed with an outlet port 44, these ports being connected with the pipes 28 and 42 as shown in Figs. 1 and 4. Threaded -or otherwise secured to the forward end of the head 62 is an elongated outer tubular casing 64 which carries at its forward end a spray nozzle indicated as a whole by the numeral 66. The spray nozzle shown in Fig. 4 comprises a member 68 in screw threaded engagement with the casing 64 and a nozzle tip 7 O which is secured to an externally threaded shank 72 of the member 68 which is secured to the end of the casing 64. Between the end of the shank 72 and the inner wall 74 of the nozzle tip is secured a disc 76 having a plurality of slots 78 (Figs. 5 and 7) formed therein which extend tangentially outward from a central circular opening 80 formed in the disc. The member 68 of the nozzle is formed with a series of ports 82 which establish communicationbetween a chamber 84 formed by the casing 64 and an annular groove 88 formed in the front face of the shank 72 of the nozzle. The

-member 68 is formed with an axial cylindrical chamber 90 which aligns with the opening 80 la the disc 76 and also with a chamber 92 formed in the nozzle tip '70; The forward end of the chamber 92 is of conical formation as indicated at 94 and an outlet orifice 96 is formed in the tip through which the fuel 'is discharged. Liquid fuel flows from the port 38 throu h the chamber 84 and ports 82 through t e tangential slots 78 and has .a whirling motion imparted thereto and is discharged from the. outlet orifice s-9fi in a spray of conical formation.

A rod 100 forms a needle valve and is provided with a bevelled end 98 adapted to valve is in the closed position shown in full lines in Fig. 4.

Located concentrically within the casing 64 is an inner tubular member 104 which is held in suitable seats 106 and 108 formed respectively in the member 68 and the burner head 62, suitable gaskets being provided as shown. The tubular member 104 forms a conduit 110 through which the fuel can flow to a chamber 112 formed by suitable cavities in the valve head 62 and the valve body 60. The rear portion of the chamber 112 is tapered to form a valve seat 114. A valve 116 is carried by a threaded portion of the rod and a jam nut 118 is provided to securely hold the valve in place on the rod. The valve 116 is adapted to be seatedagamst the seat 114 to either prevent communication between the chamber and the outletport 44 or else control the volume of fuel passing therebetween.

A plunger 120 is secured to a threaded portion 122 atv the rear end of the valve rod 100, a lock nut 124 being provided to prevent relative movement between the plunger and the rod. The plunger 120 operates in a cylindrical chamber 126 formed in the rear end of the burner body 60 and a spring 128 is adapted to hold the plunger and valve rod 100 in the position shown so that the at a pressure great enough to compress the spring 128 the valve rod 100 will be retracted and permit fuel to be discharged through the orifice 96.

A head 132 is secured bysuitable screw threads to the rear end of the burner body 60. This head carries rearwardly extending arms 134 which support a hub 136 in which is seated a block 138 which forms an adjlistable seat. for the spring 128. This block is provided with a hexagonal head 139 by which the block may be turned to vary the tension of the spring. Extending axially through the hub 138 is a screw 140 having a squared end 142 which is adapted to be turned so as to limit the backward movement of the valve rod 100. By means of this adjustment, if desired, the valve 116 may be prevented from closing tight upon its seat 114.

' The burners as above constructed provide means whereby the fuel is continuouslycirculated through the burners at the opposite ends of the furnace regardless of which burner is supplying the fuel and the control is such that when one burner is injecting the fuel into the furnace at one end, the injection of the fuel is automatically cut off at the opposite end of the furnace. This operation is made possible by the use of the movable plunger 120 and the valves 100 and 116 actuated thereby.

It will be readily appreciated that the spring 128 and plunger 120 can impart either a closing or openin movement to the needle valve 100. The va ve 116 is carried by and therefore is moved simultaneously with the needle valve 100 and the parts are so arranged that when the needle valve moves in the direction to open the outlet orifice in the end of the nozzle, the valve116 receives a closing movement. It will be furtherappreciated that the pressure exerted on the plunger by the fuel supplied each burner can be alternately varied by manipulation of the three-way valve shown in Fig. 3. By adjusting the screw 140 the movement of the needle valve 100 can be varied to control the volume of fuel discharged through the outlet orifice of the nozzle.

In operation assuming that the three-way valve 24 is in the position shown in Fig. 3, fuel under a pressure, for example of pounds, will be pumped from the tank 16 through pipes 18, 20 and 22 to the pipe 26. The fuel enters the inlet port 38 of the burner 34 and passes through the chamber 84 to the forward part thereof. Part of the fuel passes through port 130 and exerts sulfi- .cient pressure on the plunger 120 to cause the needle valve to be retracted from its seat 94. The fuel then escaping through the tangential slots 78 in the plate 7 6 has a whirling motion imparted thereto and is ejected in a fine spray from the outlet orifice 96 of the nozzle. When the maximum quantity of fuel is to be injected into the furnace from the nozzle, the adjusting screw 140 will be turned to such position that plunger 120 will cause the needle valve to be fully retracted from its seat 94 and the valve 116 will close communication between the chamber and the return fuel pipe 40 of the burner 34. If desired the screw 140 can be set to prevent the valve 116 from entirely cutting off communication between the outlet port 44 and the chamber 110 when the needle valve is retracted so' that a certain amount of fuel will continuously circulate back to the return pipe 46. I

When fuel is being injected at one end of the furnace, for example, from the burner 34, Fig. 1, the spray from burner 36 will be cut off because its needle valve 100 will be in closed position as shownin Fig. 4, it

being remembered that the'three-way valve is not in position to supply high pressure fuel to the pipe 28, and the spring 128 is sufiicient to hold the plunger 120 in the position shown in Fig. 4. The fuel which is fed from the pipe 20 through the by-pass 50 passes through a throttle valve 58 which is arranged so that fuel thus by-passed has a pressure-of approximately-20 pounds. The spring 128 is of sufficient strength to Withstand this pressure and, therefore, the outlet orifice 96 of the burner 36 is closed, by its needle valve 100. The valve 116 of the Qll burner 36 will be in the full line open position shown in Fig. 4, and thus permit the fuel to circulate continuously from the pipe 28 through inlet port 38, chamber 84, ports 82 and rearwardly through the chamber 110 past the valve 116 to the outlet port 44 and bv way of pipe 42 to the return main 46. By this arrangement it is seen that the spray is cut off from the burner 36 at the outgoing end of the furnace and yet a circulation of fuel oil is maintained therethrough which is sufficient to adequately cool the burner and thus prevent its destruction by the hot gases coming from the furnace chamber on their way to the down-take ports. When the furnace is to be reversed the handle 25 of the three-way valve 24 is moved to the dotted line position shown in Fig. 1 which causes fuel oil under high pressure to flow through the pipe 28 so that the needle valve 100 in the burner 36 will be retracted and the spray will be injected at the corresponding end ofthe furnace. The high pressure fuel will then be cut off from the burner 34 and fuel at a lower pressure will circulate through this burner, the fuel being supplied from the pipe 20 through the by-pass 48.

My invention eliminates the necessity of I the hot furnaces to regulate the air and steam used in former types of burners.

There are several objections to the introduction of steam in open hearth furnaces one being a thermal loss due to the necessity of dissociating the steam into hydrogen and oxygen, and another being that the hydrogen attacks the white hot silica brickwork of the furnace and causes its premature destruction. Furthermore the presence of water vapor'causes a lower flame temperature,

Though I have described with great particularity the details of the embodiment of the invention herein shown, it is not to be construed that I am limited thereto as changes in airangement and substitution of equivalents may be made by those skilled in the art without departing from the invention as defined in the appended claims.

What I claim is:

1. In combination with a metallurgical furnace, burners for injecting liquid fuel at opposite ends of the furnace, means for continuously circulating the fuel through said burners and means including a manually operated valve for controlling the injection of the fuel whereby it is injected at one end of the furnace and cut off at the other end of the furnace.

2. In combination with a metallur ical furnace, burners located at opposite en s of the furnace, means for circulating the fuel in contact with said burners to cool the same, means actuated by the pressure of the fuel supplied to the burners for controlling the discharge of fuel into the furnace and means including a manually controlled valve whereby fuel of high and low pressure is alternately supplied to the burners at opposite ends of the furnace.

3. In combination with a metallurgical furnace, burners located at opposite ends of the furnace, a respective needle valve in each burner adapted to open or close the outlet orifice of a respective burner, a spring arranged to hold each needle valve in one position, 'a plunger adapted to move each needle valve to another position and means whereby fuel at respectively high and low pressure acts alternately on each plunger so that the fuel is alternately supplied and cut off at opposite ends of the furnace.

4. In combination with a metallurgical furnace, burners located at opposite ends of the furnace, means for alternately varying the pressure of the fuel supplied to the-burners,

' and means carried by each burner arranged to be actuated by a variation in the pressure of fuel supplied thereto for controlling the injection of fuel into the furnace.

5. In combination with a metallurgical furnace, burners locatedat opposite ends of the furnace, means for alternately varying the pressure of the fuel supplied to the burners, fuel inlet and outlet pipes connected to said burners, means for providing a circulasame, and means carried by each burner arranged to be actuated by a variation of the pressure at which the fuel is supplied thereto for controlling communication between said fuel inlet and outlet pipes.

6. A burner for liquid fuel including a spray nozzle, means for imparting a whirlmg motion to the fuel to assist in atomizing the same, a needlevalve for opening" and closing the outlet orifice of said spray nozzle, inlet and outlet pipes connected to said burner, means for circulating the fuel through said nozzle from said inlet pipe to said outlet pipe to cool the burner and a valve movable with said needle valve for controlling communication between said fuel inlet and said fuel outlet.

7. A burner for liquid fuel including a spray nozzle, means for imparting a whirling motion to the fuel to assist in atomizing the same, a needle valve for opening and closing the outletorifice of said spray nozzle, I

inlet and outlet pipes connected to said burner, means for circulating the fuel through said nozzle from said inlet pipe to said outlet pipe to cool the burner and means for simultaneously moving said needle valve and controlling the circulation of fuel from said inlet pipe to said outlet pipe.

8. A burner for liquid fuel including a nozzle having an outlet orifice, inlet and outletports, means for conveying fuel to said outlet orifice, a needle valve for controlling the discharge of fuel through said orifice, a valve for controlling the circulation of fuel from said inlet port to said outlet port, said valve being so arranged that when the needle valve is given an opening movement said control valve is given a closing movement and vice versa.

9. A burner for liquid fuel including a nozzle having an outlet orifice, inlet and outlet ports, means for conveying fuel to said outlet orifice, a needle valve for controlling the discharge of fuel through said orifice, a valve for controlling the circulation of fuel from said inlet port to said outlet port, said valve being so arranged-that when the needle valve is given an opening movement said control volve is given a closing movement and vice versa, and means actuated by the theneedle valve is given .an opening movement said control valve is givenv a closing movement and vice versa, a spring for holding both of said valves in one position, and means actuated by the pressure of the fuel supplied for moving both valves to their other position.

11. A burner including a spray nozzle provided with means for atomizing liquid fuel, an outer shell supporting the spray nozzle, a needle valve extending longitudinal- 1y through the said shell and adapted to open and close the outlet orifice of said spray nozzle, a fuel inlet connected with said shell, a body to which said shell is secured, said body having a chamber formed therein, a

= plunger movable in said chamber, an outlet for fuel communicating with said fuel inlet, and means actuated by said plunger for cutting off communication between said fuel inlet and outlet.

12. A burner having an inlet pipe and an outlet pipe connected thereto through which the fuel is adapted to continuously circulate, an elongated shell secured to said burner and having a spray nozzle secured to one end thereof, means for providing a circulation between said inlet pipe and said outlet pipe through said nozzle and said shell and auto matic means controlled by the pressure of the fuel supplied to the burner for controlling the rate of the passage of fuel from the inlet pipe to the outlet pipe. v

13. A burner comprising a body portion having an inlet pipe and an outlet pipe connected thereto, an elongated shell secured 35 to said body and having a spray nozzle secured to one end thereof, means for providing a circulation between said inlet pipe and said outlet pipe, means for automatically controlling the rate ofpassage of fuel from the inlet pipe to the outlet pipe, and means movable with the last named means for controlling the fuel discharged from said spray nozzle.

14. A burner adapted to atomize tar or similar heavy fuels comprising an elongated body structure formed with inner and outer longitudinal chambers, a fuel inlet communicating with the outer chamber and a fuel outlet communicating with the inner chamber which provide means for continuously circulating the fuel in contact with the burner so as to heat the fuel and cool the burner and automatically actuated means for varying the rate at which said fuel flows through the burner.

15. In combination with an open hearth furnace, a plurality of burners having elongated bodies extending into the furnace, each burnerhaving an inner and outer hollow shell-like body with a space between them,

fuel inlet and outlet ducts connected with each burner providing means for circulating fuel through the burners to cool the same and an automatically actuated valve in each burner for controlling the rate of flow of 65 fuel therethrough.

In witness whereof, I have hereunto signed my name.

JAMES H. GRAY. 

